[R] indexing data.frame columns

Consider the data.frame: df - data.frame(A = c(1,4,2,6,7,3,6), B= c(3,7,2,7,3,5,4), C = c(2,7,5,2,7,4,5), index = c(A,B,A,C,B,B,C)) I want to select the column specified in 'index' for every row of 'df', to get goal - c(1, 7, 2, 2, 3, 5, 5) This sounds a lot like the indexing-by-a-matrix you

Re: [R] indexing data.frame columns

On Thu, Apr 5, 2012 at 1:40 PM, Peter Meilstrup peter.meilst...@gmail.com wrote: Consider the data.frame: df - data.frame(A = c(1,4,2,6,7,3,6), B= c(3,7,2,7,3,5,4), C = c(2,7,5,2,7,4,5), index = c(A,B,A,C,B,B,C)) I want to select the column specified in 'index' for every row of 'df', to get

Re: [R] indexing data.frame columns

Le jeudi 05 avril 2012 à 12:40 -0700, Peter Meilstrup a écrit : Consider the data.frame: df - data.frame(A = c(1,4,2,6,7,3,6), B= c(3,7,2,7,3,5,4), C = c(2,7,5,2,7,4,5), index = c(A,B,A,C,B,B,C)) I want to select the column specified in 'index' for every row of 'df', to get goal - c(1,